Author: Calaga, R.
Paper Title Page
MOODN4 Beam Losses Due to Abrupt Crab Cavity Failures in the LHC 76
 
  • R. Calaga
    BNL, Upton, Long Island, New York, USA
  • T. Baer, J. Barranco, R. Tomás, J. Wenninger, F. Zimmermann
    CERN, Geneva, Switzerland
  • B. Yee-Rendon
    CINVESTAV, Mérida, Mexico
 
  Funding: This work partially supported by the US Department of Energy through the US LHC Accelerator Research Program (LARP).
A major concern for the implementation of crab crossing in a future high-luminosity LHC (HL-LHC) is machine protection in an event of a fast crab-cavity failure. Certain types of abrupt crab-cavity phase and amplitude changes are simulated to characterize the effect of failures on the beam and the resulting particle-loss signatures. The time-dependent beam loss distributions around the ring and particle trajectories obtained from the simulations allow for a first assessment of the resulting beam impact on LHC collimators and on sensitive components around the ring. The simulation results are used to derive tolerances on the maximum rate of change in crab-cavity phase and amplitude which can be allowed with regard to machine safety.
 
slides icon Slides MOODN4 [1.620 MB]  
 
TUOAN2 High Luminosity Electron-Hadron Collider eRHIC 693
 
  • V. Ptitsyn, E.C. Aschenauer, M. Bai, J. Beebe-Wang, S.A. Belomestnykh, I. Ben-Zvi, M. Blaskiewicz, R. Calaga, X. Chang, A.V. Fedotov, H. Hahn, L.R. Hammons, Y. Hao, P. He, W.A. Jackson, A.K. Jain, E.C. Johnson, D. Kayran, J. Kewisch, V. Litvinenko, G.J. Mahler, G.T. McIntyre, W. Meng, M.G. Minty, B. Parker, A.I. Pikin, T. Rao, T. Roser, B. Sheehy, J. Skaritka, S. Tepikian, R. Than, D. Trbojevic, N. Tsoupas, J.E. Tuozzolo, G. Wang, Q. Wu, W. Xu, A. Zelenski
    BNL, Upton, Long Island, New York, USA
  • E. Pozdeyev
    FRIB, East Lansing, Michigan, USA
  • E. Tsentalovich
    MIT, Middleton, Massachusetts, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
We present the design of future high-energy high-luminosity electron-hadron collider at RHIC called eRHIC. We plan on adding 20 (potentially 30) GeV energy recovery linacs to accelerate and to collide polarized and unpolarized electrons with hadrons in RHIC. The center-of-mass energy of eRHIC will range from 30 to 200 GeV. The luminosity exceeding 1034 cm-2 s-1 can be achieved in eRHIC using the low-beta interaction region with a 10 mrad crab crossing. We report on the progress of important eRHIC R&D such as the high-current polarized electron source, the coherent electron cooling and the compact magnets for recirculating passes. A natural staging scenario of step-by-step increases of the electron beam energy by builiding-up of eRHIC's SRF linacs and a potential of adding polarized positrons are also presented.
 
slides icon Slides TUOAN2 [4.244 MB]  
 
THP006 Status of High Current R&D Energy Recovery Linac at Brookhaven National Laboratory 2148
 
  • D. Kayran, Z. Altinbas, D.R. Beavis, I. Ben-Zvi, R. Calaga, D.M. Gassner, H. Hahn, L.R. Hammons, A.K. Jain, J.P. Jamilkowski, N. Laloudakis, R.F. Lambiase, D.L. Lederle, V. Litvinenko, G.J. Mahler, G.T. McIntyre, W. Meng, B. Oerter, D. Pate, D. Phillips, J. Reich, T. Roser, C. Schultheiss, B. Sheehy, T. Srinivasan-Rao, R. Than, J.E. Tuozzolo, D. Weiss, W. Xu, A. Zaltsman
    BNL, Upton, Long Island, New York, USA
 
  An ampere-class 20 MeV superconducting energy recovery linac (ERL) is under construction at Brookhaven National Laboratory (BNL) for testing of concepts relevant for high-energy coherent electron cooling and electron-ion colliders. One of the goals is to demonstrate an electron beam with high charge per bunch (~5 nC) and low normalized emittance (~5 mm-mrad) at an energy of 20 MeV. A flexible lattice for the ERL loop provides a test bed for investigating issues of transverse and longitudinal instabilities and diagnostics for CW beam. A superconducting 703 MHz RF photo-injector is considered as an electron source for such a facility. We will start with a straight pass (gun/cavity/beam stop) test for gun performance studies. Later, we will install and test a novel injection line concept for emittance preservation in a lower-energy merger. Here we present the status and our plans for construction and commissioning of this facility.  
 
FROAN1 The European Spallation Source 2549
 
  • S. Peggs, H. Danared, M. Eshraqi, H. Hahn, A. Jansson, M. Lindroos, A. Ponton, K. Rathsman, G. Trahern
    ESS, Lund, Sweden
  • S. Bousson
    IPN, Orsay, France
  • R. Calaga
    BNL, Upton, Long Island, New York, USA
  • G. Devanz, R.D. Duperrier
    CEA/DSM/IRFU, France
  • J. Eguia
    Fundación TEKNIKER, Eibar (Gipuzkoa), Spain
  • S. Gammino
    INFN/LNS, Catania, Italy
  • S.P. Møller
    ISA, Aarhus, Denmark
  • C. Oyon
    SPRI, Bilbao, Spain
  • R.J.M.Y. Ruber
    Uppsala University, Uppsala, Sweden
  • T. Satogata
    JLAB, Newport News, Virginia, USA
 
  The European Spallation Source (ESS) is a 5 MW, 2.5 GeV long pulse proton linac, to be built and commissioned in Lund, Sweden. The Accelerator Design Update (ADU) project phase is under way, to be completed at the end of 2012 by the delivery of a Technical Design Report. Improvements to the 2003 ESS design will be summarised, and the latest design activities will be presented.  
slides icon Slides FROAN1 [1.650 MB]  
 
FROBS6 High Current SRF Cavity Design for SPL and eRHIC 2589
 
  • W. Xu, I. Ben-Zvi, R. Calaga, H. Hahn, E.C. Johnson, J. Kewisch
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy
In order to meet the requirements of high average current accelerators, such as the Superconducting Proton Linac (SPL) at CERN and the electron–ion collider (eRHIC) at BNL, a high current 5-cell SRF cavity, called BNL3 cavity, was designed. The optimization process aimed at maximizing the R/Q of the fundamental mode and the geometry factor G under an acceptable RF field level of Bpeak/Eacc or Epeak/Eacc. In addition, a pivotal consideration for the high current accelerators is efficient damping of dangerous higher-order modes (HOM) to avoid inducing emittance degradation, cryogenic loading or beam-breakup (BBU). To transport the HOMs out of the cavity, the BNL3 cavity employs a larger beam pipe, allowing the propagation of HOMs but not the fundamental mode. Moreover, concerning the BBU effect, the BNL3 cavity is aimed at low (R/Q)Qext for dangerous modes, including dipole modes and quadrupole modes. This paper presents the design of the BNL3 cavity, including the optimization for the fundamental mode, and the BBU limitation for dipole and quadrupole modes. The BBU simulation results show that the designed cavity is qualified for high-current, multi-pass machines such as eRHIC.
 
slides icon Slides FROBS6 [2.577 MB]